Cloud computing services that serve large numbers of users can require multiple server systems and very high data rate communication connections among data centers that are separated by distances that are typically as much as 10 km to 150 km or more. As a result, optical fiber communications systems have been deployed to provide the necessary communication connections as such systems provide low signal losses and high bit rates. To take advantage of the wide bandwidth offered by fiber-based systems, single mode fiber connections are provided and wavelength division multiplexing (WDM) techniques are used in which multiple wavelengths carry independent data streams. However, at typical separation distances required by cloud service provides, fiber chromatic dispersion can limit available data rates.